1. Field of the Invention
This invention relates to a multi-wavelength target system that includes a single target pattern including at least one visible target, at least one near infrared target and at least one far infrared target in one rugged and rigid assembly. These targets are accurately positioned to permit optical alignment measurements of 30 microradians angular position accuracy.
2. Description of the Prior Art
Until now, target systems for optical test collimators have included three or more separate target members optically combined together to form a single optical target pattern (i.e., a composite target). Unfortunately, these target patterns failed to attain and retain the precise target registration required, typically less than 20 microradians, for making optical system alignment measurements of about 30 microradians angular accuracy with such target systems.